Big beautiful eyes can be a warning sign

There is one compliment that costs me more time than any other. Wah, look at those big beautiful eyes. Aunties say it, neighbours say it, the photographer at the one-month party says it, and everybody means it warmly. Nearly always they are right and the baby simply has lovely large eyes.

Occasionally they are describing a sign. A baby's eye that is genuinely getting bigger, especially if the clear window at the front looks hazy rather than glassy, is one of the few things in a newborn that I want to see this week rather than at the next check. This article is about telling those two babies apart, and about why the compliment is the reason the second one arrives late.

Everyone says my baby has beautiful big eyes. Could that be a problem?

Usually not. Most big-eyed babies are healthy babies with big eyes, and the shape of a face is inherited like everything else. What changes the picture is company. Large eyes plus constant watering, or a cornea that looks cloudy, or a baby who screws her eyes shut in ordinary daylight, is a different sentence altogether.

A hospital pathway written for GPs puts those three together and calls the result an urgent referral to an acute eye clinic: the cornea appears cloudy or grey, the eyes or corneas look bigger than usual, and the child is unusually sensitive to light. Not a phone call next month. Not a wait and see.

The other thing that matters is change. A baby whose eyes have always looked large is telling you about her face. A baby whose eye looks bigger this month than it did last month, or bigger on one side than the other, is telling you about pressure.

What is glaucoma doing in a baby's eye?

The same thing it does in an adult eye, with one difference that changes everything. Fluid made inside the eye cannot drain out properly, so pressure builds, and pressure damages the optic nerve. In a baby, the wall of the eye is still soft, so instead of only pressing inward, the pressure stretches the eye outward.

That stretching is why a baby announces it in a way an adult never could. The eye grows. The cornea, the clear window at the front, stretches too, and when it stretches it loses its clarity and turns hazy or grey. Doctors have an old name for the enlarged eye, buphthalmos, which translates roughly as ox eye, and it is as literal as it sounds.

So the signs are not subtle once you know to look. Too much tearing. Pain in bright light. A large or cloudy cornea. Those three, in that order, are what the paediatric eye body lists for primary congenital glaucoma, and they are all things a parent can see across a cot.

Her eye waters all the time. Is it a blocked tear duct or something worse?

Almost certainly a blocked tear duct. More than five in a hundred babies have a watery, sticky eye from one, and about nine in ten of those clear on their own during the first year. Watering is the commonest complaint about baby eyes I see, and glaucoma is a rare cause of it.

But watering is also the sign the two conditions share, which is why the paediatric eye body specifically tells doctors to check a watery baby's eye for the less common serious causes, glaucoma among them. The difference is not the amount of tears. It is what comes with them. A blocked duct gives you a wet, sometimes sticky eye and a baby who is otherwise entirely unbothered, and it is comfortable in the light. Glaucoma gives you a wet eye plus discomfort: squeezing the lids shut, turning away from a window, and over weeks a cornea that stops looking crystal clear.

Blocked tear ducts, and what is normal about them covers the ordinary version in full, including the massage that helps. Bring this one to me instead if the watering travels with light sensitivity, or with an eye that is changing size or clarity.

She cries in daylight and keeps her eyes shut. Why?

Because a stretched, hazy cornea scatters light, and scattered light hurts. Light sensitivity in a baby is not fussiness and it is not a preference. It is one of the three named symptoms, and it is often the one a parent notices first because it happens every single time you carry her outside.

What you see is a baby who buries her face in your shoulder at the car park, who cannot be photographed near a window, who screws her lids tight and keeps them tight. That lid squeezing has its own name in clinic, blepharospasm, and paired with watering it is a combination I take seriously in a baby every time.

None of this makes your baby unusual to talk about. Plenty of newborns dislike bright light briefly. The pattern that counts is persistent, repeatable, and getting worse rather than better, particularly alongside an eye that waters without a sticky discharge.

How quickly does this need to be seen?

This week, and today if the front of the eye looks cloudy. The reason is not that childhood glaucoma is common. It is that in childhood it can be aggressive, and sight can be lost quickly. Around eight in ten cases are diagnosed during the first year of life, which tells you how early this shows itself and how early it needs answering.

Practically: take a photograph. The referral pathway asks for a photo of the eye attached to the referral where possible, and a clear picture taken in daylight of both eyes side by side is genuinely useful to whoever sees her next. It also removes the awkward problem of a baby whose worst sign has settled by the time you reach the clinic.

Then say the words out loud when you book. Not "her eye is watery", which sounds like every second baby, but "her eye waters, she cannot bear the light, and I think this eye looks bigger". That sentence moves an appointment. The same principle applies to a white glow in a flash photo, and it is the single most useful thing a parent can do with a worry.

How rare is it, and does it run in families?

Rare. In Western countries about one baby in ten thousand is born with primary glaucoma, and in the Middle East the figure quoted is about one in two thousand five hundred. No comparable Malaysian figure has been published that I can point you to, so I will not invent one.

Family history matters but does not decide it. Somewhere between one and four in every ten cases of primary congenital glaucoma run in families, which means most babies who have it have no family history at all. If you have it in your family, say so at the first eye check rather than waiting to be asked, and the schedule of a baby's first eye checks tells you when those moments are.

There is also a secondary group, where the pressure problem comes from something else. Certain syndromes present at birth, eye injury, previous eye surgery, and steroids, including those in eye drops, tablets and inhalers, can all raise pressure. Babies who have had cataract surgery in the first six months are watched for years for exactly this, because about one in five develop glaucoma within a decade.

What happens if she does have it?

An examination first, and in a baby that usually means under anaesthetic, because measuring pressure and looking at the drainage angle properly cannot be done on a wriggling infant. Then treatment, and for primary congenital glaucoma the main treatment is surgery to open the drainage, not drops.

I would rather be honest about the shape of it. Children often need more than one operation. Many still need drops or tablets afterwards. Follow-up runs for years, not months, because the pressure has to be watched as she grows. Glaucoma also drags other problems along with it, short-sightedness, a lazy eye, and eye movement problems, and each of those gets treated in its own right.

What I can tell you is that with prompt diagnosis and surgery, some children with congenital glaucoma stand a good chance of normal or near-normal vision for the rest of their lives, and that even with treatment some vision loss can still happen. Early diagnosis, proper treatment and regular follow-up are what tilt that balance. Which brings us back to the compliment. If your baby has big beautiful eyes and nothing else, enjoy them. If she has big eyes and a watering, light-hating, hazy one, let me be the one who tells you it is nothing.

Common questions

References

1. AAPOS · Glaucoma in children · aapos.org
2. American Academy of Ophthalmology · Childhood glaucoma · www.aao.org
3. Moorfields Eye Hospital · Children's eye conditions management, glaucoma (suspected) referral pathway · www.moorfields.nhs.uk
4. AAPOS · Nasolacrimal duct obstruction (blocked tear duct, and the serious causes of tearing to exclude) · aapos.org
5. AAPOS · Amblyopia (lazy eye) · aapos.org
6. NHS · Red eye · www.nhs.uk

By Dr Chan Li Yen. General information only. It does not replace a consultation. If you are worried about your child's eyes or vision, please see an eye doctor.